View Single Post
  #31   Report Post  
Old March 7th 07, 06:01 PM posted to rec.radio.amateur.moderated
Michael Coslo Michael Coslo is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 828
Default Tube equipment question

wrote:
On Mar 6, 4:30?pm, Michael Coslo wrote:




I have gathered the parts to make just that!. I'd have it up now, but I
switched to a coax fed antenna for a while, and built a more traditional
tuner. In the interim I went back to balanced line.


The AG6K tuner can be used with balanced or unbalanced
line.


I should have been more clear about the reasons. The tuner that I made
is a massively retro unit that is kinda pretty. Cherry finished wood
face, with real old time knobs and cranks. If I went to the balanced one
now, I'd need to start over again. I will eventually build the AG6K type
balanced tuner of course, but want to enjoy this one for a while.



Reg Edwards' DIPOLE3 program can be a big help in
figuring out the shack-end impedance of various
antenna/transmission line combinations.


I have all his programs. Upon his demise, his family and a number of
interested amateurs made sure to archive and distribute them. We miss
Reg over on rraa.



Although not mentioned in the article, the roller inductors
could be replaced by a pair of tapped coils and a double-pole switch.


The tuner can be hot switched, I assume?

Automatic tuners are not new to amateur radio, btw.
An automatic balanced tuner was described in QST for July, 1952. It
would automatically retune itself within
an amateur band. Changing bands meant changing coils, but once that
was done the tuner would do the rest automatically.


Thanks for the reference, Jim. It should be interesting to see how they
did it then.

- 73 de Mike KB3EIA -